The Food and Drug Administration warned that anyone prescribed the sleeping medication Lunesta might want to start their dosages at half strength, to about 1 milligram.

The federal agency ordered the manufacturer, Sunovion Pharmaceuticals, to change its warning labels to reflect the new FDA recommendations, which are a scale-back of the current 2 milligram dose, The New York Times reported.

The FDA’s latest recommendation comes in part from research that involved 91 adults at the Surrey Clinical Research Center in Britain. The study found that 3 milligrams of Lunesa impairs memory and motor skills the next day and that the recommended 2 milligrams could prove a challenge for driving, memory and fine-motor skills for up to 11 hours after ingesting.

The recent approval by the Food and Drug Administration (FDA) of paroxetine (Brisdelle, Noven) for the treatment of moderate-to-severe vasomotor symptoms associated with menopause was distinctive for at least two reasons. First, it offered the first nonhormonal option to women who cannot or do not want to use hormonal medications to treat their menopausal vasomotor symptoms. Second, the approval ran counter to the recommendation of the FDA Reproductive Health Drugs Advisory Committee, which had concluded, by a vote of 10 to 4, that the overall benefit–risk profile of Brisdelle did not support approval.

For decades, hormonal therapy had been the only FDA-approved treatment for menopausal vasomotor symptoms. Hormonal therapy is highly effective for treating vasomotor symptoms, but health risks in some women became apparent about a decade ago, with the release of reports from the Women's Health Initiative. Owing to these reports, many women either have chosen not to use hormonal therapy to treat their symptoms or have not been offered such therapy because of coexisting conditions. Overall, use of hormonal therapy has decreased considerably in the past decade — a trend that underscores an unmet need for a nonhormonal treatment option for vasomotor symptoms.

The efficacy of Brisdelle was established in two randomized, double-blind, placebo-controlled, multicenter clinical trials. More women who used Brisdelle than women who used placebo considered the reduction in frequency of their hot flushes to be clinically meaningful. In addition, Brisdelle remained efficacious at 6 months, the latest time point assessed. This is an important finding, because a lack of efficacy at 6 months after treatment initiation would call into question its usefulness for this fairly chronic condition.

Brisdelle's modest efficacy and concerns about suicidal ideation certainly influenced the advisory committee's 10-to-4 vote against approval. But recognizing that no hormone-free drug product had been approved to treat vasomotor symptoms, and after careful review of the efficacy results, the FDA concluded that Brisdelle offers a clinically meaningful benefit for some menopausal women. In addition, the Brisdelle clinical trials did not identify any new safety concerns regarding paroxetine.